JPH0372739B2 - - Google Patents

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a yarn supply control device for monitoring and controlling the tension and amount of yarn supplied to a yarn using device such as a circular knitting machine. Regarding.

[Prior Art] If one spinning yarn feeding machine in a circular knitting machine with multiple feeding devices has a different yarn supply amount or yarn tension from other spinning yarn feeding machines, the pattern will be disturbed and the appearance of the product will be affected. The thread tension and supply amount are monitored using manual instruments in each knitting section to ensure that there are no changes that could lead to defective products. is known to be thoroughly tested. However, such inspections have already produced a significant amount of defective products by the time changes that lead to defective products are discovered.

In contrast, a yarn supply means for electronically adjusting the tension of the yarn is disclosed in German Patent No. 3,627,731. The yarn supply means is provided with a yarn wheel which is rotatably supported and which supplies the yarn substantially without slipping. The yarn wheel with the yarn guide element is driven by a step motor which is controlled by an electronic control unit. The electronic controller is essentially a voltage controlled oscillator (VCO) that generates step pulses for the step motor. This VCO receives an input signal from a yarn tension sensing means arranged in the yarn travel path behind the yarn wheel. a yarn tension characteristic signal is obtained from the yarn tension detection means;
Based on this signal, the VCD adjusts the thread tension to be substantially constant.

This known yarn supply means uses two types of electronic signals: a signal relating to the tension of the yarn and a signal relating to the amount of yarn supplied as a frequency signal at the output of the oscillator, i.e. the amount of yarn spun per unit time. It uses signals.

[Problem to be Solved by the Invention] The problem of the present invention is to automatically monitor the tension and supply amount of the spun yarn to set various values and adjust them to desired values regarding the tension and supply amount of the spun yarn. It is an object of the present invention to provide a spinning yarn supply control device that eliminates the need for.

[Means and actions for solving the problem] A measuring device that supplies an output signal indicating spinning yarn supply parameters such as the moving speed of the spinning yarn and the amount used per unit time to each feed is a measuring device such as a knitting feeder of a knitting machine. It is arranged between the yarn supplying yarn usage elements.
According to the invention, a reference signal is generated which is formed by a yarn measurement signal obtained from some, preferably from all, of the yarn measurement circuits or yarn detection circuits for the knitting feeder. Ru. Next, feed the yarn to either knitting feeder,
A bias signal is generated by comparison with the reference signal generated based on the plurality or all of the measurement circuits. controlling the yarn supply means associated with each bias signal to reduce the difference between the actual yarn supply parameter reflected in the detected signal and a reference having a predetermined tolerance width; Make it zero.

The novel yarn feeding device according to the invention has means for generating a yarn quantity reference value which is dependent on all the measurement signals obtained, so that the reference value itself is automatically adjusted according to changes in the conditions. adjusted. The measuring signal of each measuring circuit is compared with all other measuring signals at once, and only the particular measuring signal which deviates from the yarn quantity reference value by more than a permissible width is reported via the deviation or error signal circuit. Ru. Therefore, the yarn quantity reference value is a type of variable yarn quantity reference value that is influenced by the entire measured signal.

The yarn quantity reference value generating means comprises a measuring circuit with a defined characteristic output resistance and a series of resistors connected in series with the output of the measuring circuit and the first connection line. The output terminals of all the measuring circuits are connected to the first connection line via a series of resistors. The other output terminal is connected to a second common connection line, which is the ground line of the circuit. In this circuit, a current is generated in a series of resistors that indicates the deviation of a particular measurement signal from a variable yarn rate reference value. If the series of resistors are identical to each other and the inherent output resistances are also identical to each other, various relationships can be easily calculated and analyzed.

The sensitivity of the error or bias alarm circuit can be easily changed by dividing each series of resistors into at least two partial resistors connected in series, so that the partial voltage can be adjusted to a particular bias signal circuit. It can be taken out by

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 shows a yarn supplying device 1. As shown in FIG. The yarn supply device 1 has a housing 2 . The housing 2 has a holder 3 for fixing the yarn supply device 1 to a circular frame ring (not shown) of a knitting machine. On the side of the holder 3, an electrical connection device (not shown) for supplying electricity to the yarn supply device 1 is located. Located in the upper part of the housing 2 is an electric step motor 4 (not visible in FIG. 1, see FIG. 2). The shaft of the electric step motor 4 projects through a suitable opening in the front wall of the housing 2. On this projection of the shaft, a spinning wheel 5 driven by the shaft is fixed so as not to rotate relative to the shaft. A fixed yarn guide element is provided in the housing 2 in conjunction with the yarn wheel 5. The fixed yarn guide element is attached to a holder 6 attached to the housing 2.
and a yarn eyelet 8 located in the housing 2 on the yarn outlet side of the yarn wheel 5. For monitoring and controlling the yarn, a yarn plate brake and a yarn inlet sensor 11 are provided below the yarn eyelet 7, ie between the yarn eyelet 7 and the yarn wheel 5. The yarn entrance sensor 11 monitors yarn breakage of the yarn 12 by bringing the sensor arm into contact with the yarn 12 passing through the sensor arm, and when the yarn breaks, sends an electric signal to turn off the power to a circular knitting machine (not shown). Occur.

A yarn guide arm 1 located below the yarn wheel 5 and extending axially parallel to the housing 2
4 is pivotably supported by an axis 13 parallel to the axis of the spinning wheel 5. The yarn guide arm 14 swings back and forth between two fixed catches 16 and 17 on the front side of the housing 2, so that the yarn guide arm 14 and its yarn eyelet 15 are
Construct a yarn reserve. The yarn guide arm 14 also functions as a sensor element for the rotational speed of the step motor 4 to adjust the tension or supply amount of the yarn. For this purpose, the yarn guide arm 14
is biased away from the catch 17 , ie away from the eyelet 18 , which is offset below the yarn eyelet 8 . The yarn guide arm 14 is connected to the biasing device 1, which is shown schematically in FIG.
It is energized by 9.

The position of the yarn guide arm 14 is confirmed by an electro-optical signal converter 21. The electro-optical signal converter 21 has an emission diode or LED 22 located in the housing 2 and a photoelectric converter 23 located in the light path of the LED 22. LED2
2 and the photoelectric converter 23 are attached to a holder 24 attached to the housing 2.
A dimming disk 2 is fixedly connected to a yarn guide arm 14 so as not to move relative to each other.
5 protrude and block the light path of the LED 22 by varying amounts according to the position of the yarn guide arm 14;
The amount of light from the LED 22 reaching the photoelectric converter 23 is adjusted. As a result, a voltage signal proportional to the angle of the yarn guide arm 14 is obtained. This voltage signal is passed through line 26 to a voltage controlled oscillator, i.e.
Supplied to VCO27. VCO 27 generates a step or clock pulse at its output terminal 28;
This is supplied via multi-wire line 29 to the windings of step motor 4, causing it to rotate. The clock signal of the VCO 27 is fed via a further line 31 to a frequency to voltage converter 32. The frequency-to-voltage converter 32 outputs via line 33 an analog signal with an amplitude proportional to the step frequency, in other words proportional to the amount of yarn supplied by the step motor 4. The circular shape and the amount of yarn fed into the knitting section of the knitting machine are linked to the frequency via the step angle of the step motor 4 and the diameter of the yarn wheel 5.

In a large circular knitting machine with multiple feeding devices, several yarn feeding devices or units 1 are used. Each unit supplies yarn to one knitting section of a circular knitting machine. If the knitting cams of the knitting machine are perfectly uniformly adjusted, the consumption of yarn will be the same in every knitting section. Alternatively, the machine speeds or rotational speeds will be at least the same. However, if irregularities occur in the knitting sections and the consumption of yarn in one knitting section increases or decreases compared to the consumption of yarn in other knitting sections, the knitted product will become uneven and the pattern of the product will change. To avoid this problem, the yarn shown in FIG. 3 is used to monitor the consumption of the spun yarn supplied from the yarn supply device 1 of FIG. 1 in various knitting sections. A circuit system 35 is provided.

The circuit system 35 has a measuring circuit 36, one for each knitting section, for determining the yarn consumption of the knitting section. This circuit system includes a frequency-to-voltage converter 32 of FIG. 2, the output signal of which is fed via line 33 to a grounded voltage divider in the form of voltage divider 37. Ru. A negative feedback differential amplifier 38, wired as a potentiometer amplifier, has its non-inverting input terminal connected to the sliding terminal of the voltage divider 37, and its output terminal 39 is negatively fed back to the inverting input terminal. Measuring circuit 36
receives at its output terminal 39 a defined low inherent output resistance, and the sensitivity of the measuring circuit can be adjusted by means of a voltage divider 37. That is, the ratio between the amplitude of the output signal of the output terminal 39 and the amplitude of the input signal proportional to the amount of yarn supplied can be changed.

A plurality of partial resistors 42a connected in series
The output 39 of the measuring circuit 36 is connected to a common connection line 43 via a series of resistors 41 consisting of -42c. Measuring circuits 36', 36'', etc. associated with other yarn feeding devices 1 of other knitting sections are also connected to the common line 43 via respective associated series of resistors 41', 41'', etc. The yarn feed rate is determined via a corresponding frequency-to-voltage converter 32 of the type shown in FIG.
Confirmed by 6″ etc.

The measuring circuits 36', .
3, a voltage is created between the circuit ground and the circuit ground, which depends on the output voltage of the entire measuring circuit 36,...,36'' as explained below.The circuit ground is connected to the measuring circuit 36 ,...,36'' second
At the same time, the connection line 43 is formed as an output terminal.
, forming a second common connection line carrying said voltage which serves as the yarn rate reference voltage for the bias signal circuit 44 . The bias signal circuit 44 has two differential amplifiers 45 and 46 connected in parallel on the input terminal side and functioning as a comparator. The inverting input terminal of the differential amplifier 45 is connected to the non-inverting input terminal of the differential amplifier 46.
The non-inverting input terminal of No. 5 is connected to the inverting input terminal of the differential amplifier 46. A voltage comprising a voltage drop across the series of resistors 41 or parts thereof is applied to the input terminals of both differential amplifiers 45, 46 which are thus interconnected. The non-inverting input terminal of the differential amplifier 45 is connected via a connection line 47 to the output terminal 39 of the measuring circuit 36 . On the other hand, the inverting input terminal of the differential amplifier 45 is connected to the connection line 4.
8 to one of the pickups 49 between the partial resistors 42a, . . . , 42c.

In order to store the temporary switching state of the differential amplifier 45 in a memory, two inverters 53, 5 with Schmitt trigger characteristics are connected in series.
4 is connected to the output terminal 50 of this differential amplifier 45 via a diode 51. The diode 51 has an anode connected to the output terminal 50 and a cathode connected to the input terminal of the first inverter 54 . The signal reaches the input terminal of inverter 53 from the output terminal of inverter 54 and returns from the output terminal of inverter 53 to the input terminal of inverter 54 by feedback resistor 55 . The base of an npn transistor 56 is also connected to the output of the inverter 53. The emitter of this npn transistor 56 is connected to the ground of the circuit via an LED 57 and a multiplication resistor 58. The collector of transistor 56 collects the positive supply voltage _UB .

Further, another memory element 59 is connected to the output terminal side of the differential amplifier 46. Differential amplifier 46
The output terminal of is connected via a diode 62 to the input terminal of a first inverter 63 having Schmitt trigger characteristics. The output terminal of the first inverter 63 is connected to the input terminal of a second inverter 64 having Schmitt trigger characteristics. Second
The output terminal of the inverter 64 is connected to the input terminal of the first inverter 63 via a resistor 65. Positive feedback causes memory element 59 to maintain its input state through diode 62 .

The output of the inverter 64 is the npn transistor 6
It is connected to the base of 6. transistor 66
The collector collects the positive supply voltage and the emitter connects LED57 and multiplier resistor 58 through LED67.
connected to the connection point. LED57 and LED
At this connection point with 67, there is yet another differential amplifier 6
Eight normally conduction direction non-inverting input terminals are connected. The inverting input terminal of operational amplifier 68 is connected to resistors 69 and 7 as a voltage divider.
1 receives a machine speed reference voltage based on the positive supply voltage U _B . The machine speed reference voltage is compared to the voltage on multiplication resistor 58 by differential amplifier 68 . Based on this comparison, the differential amplifier 68 generates a high "H" or low "L" binary signal at the output terminal 72.

The circuit system 35 includes one such bias signal circuit 44 for each yarn feeding device 1 of a circular knitting machine.
I have one. Each of the remaining bias signal circuits are of identical construction and are respectively designated as 44', 44'', etc. These bias signal circuits are connected to each series of associated measurement circuits 36, 36', 36''. They are connected in the same way as the resistors 41, 41', 41'', etc. Therefore, the explanation regarding the function of the bias signal circuit 44 also applies to the bias signal circuit 44', etc.

To facilitate understanding of the function of circuit system 35, the alternative circuit diagram of FIG. 4 will first be described. Assuming now that n voltage sources with the same specific resistance R and the same generated voltage U _M are connected in parallel, this has a substitute specific resistor 74 and has the same generated voltage U M as the individual voltage sources. Substitute voltage source 7 which is _M
Equal to 3. However, the substitute resistor 74
has the value R/n. If a further voltage source 77 having a resistor 78 of value R and generating a voltage of (U _M +ΔU) is connected between the terminals 75 and 76 of this substitute voltage source 73, the Kirchhoff By law, the current flowing through resistor 78 satisfies the following equation.

I=U·n/R(n+1) The current flowing through resistor 78 is directly proportional to ΔU.
That is, the voltage drop across resistor 78 is directly proportional to ΔU;
It disappears when ΔU becomes zero. The direction of the voltage drop is always opposite when ΔU has the opposite polarity of U _M of voltage source 77. On the other hand, ΔU is independent of the size of _M. On the other hand, terminals 75 and 76
The terminal voltage U′ _M between the two changes as follows.

U′ _M = U _M +ΔU/(n+1) From these equations, the terminal voltage U′ _M is U′ _M = U _M as long as ΔU is zero, and when ΔU is opposite in polarity to U _M , It becomes smaller than U _M , and becomes larger than U _M when ΔU has the same polarity as U _M.

Applying this principle to circuit system 35, the following is true. In a circular knitting machine with n+1 knitting sections, there are the same number of measuring circuits 36 and bias signal circuits 44. Each side regulating circuit has the same specific output resistance as measured at the output terminal 39 to which the series of resistors 41 are connected in parallel. The series of resistors 41 together with the inherent output resistance of the differential amplifier 38 constitute a resistor 78 having the value R shown in the substitute circuit diagram.

Assuming initially that all n+1 knitting units consume the same amount of yarn, every yarn supply unit 1 outputs a voltage signal of the same value via line 33. In this way, the yarn supply unit 1 is
In conjunction with circuit system 35 it functions as a yarn rate meter. The output signal of the yarn supply unit 1 is further processed. If the amount of yarn spun per unit time is the same in all knitting sections, the output signals of the differential amplifiers 36 of all measuring circuits 36, ..., 36'' will be the same.A series of resistors 41, 41 ′、
41'' are the same and the specific output resistances of the negative feedback differential amplifiers 38 are also the same, so that the voltage developed on the connection line 43 is equal to the output voltage of the individual differential amplifiers 38.For simplicity, the differential The amplifier 38 is
Assume that the specific output resistance is negligibly low compared to the resistor series 41. Then the differential amplifier 38
corresponds to a generated voltage U _M present in line 43 through a series of resistors 41 having value R.

If the yarn consumption of any one knitting section changes, the measuring circuit 36 associated with that knitting section
The output voltage of the differential amplifier 38 is changed from the original U _M to
Changes to U _M + ΔU. For simplicity, it is assumed that all other knits remain unchanged. There will then be a cross-current across the series of resistors 41 that is proportional to the voltage change ΔU, as described with respect to FIG. This current characterizes the addition or biased yarn consumption of the knit in question. Resistor 4
The current flowing into 1 causes a voltage drop. This voltage drop is tapped off in whole or in part across a series of resistors 41 and fed to both comparators 45 and 46.

Due to the polarity of the voltage drop, line 47 becomes line 4.
If it becomes positive by the voltage drop compared to 8, then
The voltage at output 50 changes from a value of zero to a positive value somewhat below U _B . As a result, the polarity of the diode 51 becomes the conduction direction, so the voltage changed in the direction of U _B reaches the inverter 54,
4, the output becomes a low voltage. As a result, the output of inverter 53 becomes a high voltage, and this high voltage is fed back to the input of inverter 54 via resistor 55. Even if ΔU disappears again, the differential amplifier 4
Even if the voltage at the output terminal 50 of 5 returns to its original value, the memory element 52 constituted by both inverters 53 and 54 remains switched. That is, the output of the inverter 53 remains at a high voltage.

Since the output of inverter 53 is a high voltage, transistor 56 is triggered to send current through LED 57 to multiplication resistor 58 . A voltage drop occurs across multiplier resistor 58 and is compared to a machine speed reference voltage by differential amplifier 68. Meanwhile, the machine speed reference voltage is compared to the supply voltage U _B by both voltage dividing resistors 69 and 71.

If the voltage drop across multiplier resistor 58 is greater than the machine speed reference voltage, a positive signal is produced at output 72 which is used to stop the circular knitting machine. LED
57 notifies the maintenance staff of which knitting section consumes too much yarn.

The sensitivity of the circuit system 35 can be changed by selecting which of the pickups 49 between the partial resistors 42a-42c is selected. The fewer the number of partial resistors that take out the voltage used in the differential amplifier 45, the lower the sensitivity, and the greater the number of partial resistors 42a-42c connected to the circuit, the higher the sensitivity.

If the yarn consumption of a certain knitting section then decreases, a voltage drop will occur across the series of resistors 41 of the measuring circuit 36 belonging to this knitting section. This is compared to the operating condition which has the opposite polarity. line 4
If the voltage on line 8 is positive compared to the voltage on line 47, differential amplifier 46 will generate a positive signal at output terminal 61 when a predetermined voltage difference occurs between its input terminals. This positive signal indicating that the consumption of yarn is decreasing causes the memory element 59 to be switched. This memory element functions similarly to memory element 52. Switching of memory element 59 triggers transistor 66, causing LED
67 is turned on and a corresponding voltage drop occurs across resistor 58. This voltage drop is evaluated by the differential amplifier 68 as before and converted into a stop signal for the circular knitting machine.

memory elements 52 and 59 after the problem is resolved
Both inverters 54 and 6
A grounded movable contact 79 is connected to the input terminal 3. This contact 79 allows the input terminals of the inverters 54 and 63 to be manually grounded. Due to this grounding, the output signal of the latter inverter 53 or 64 becomes L level. As mentioned earlier, this level is connected to resistor 5
5 and 65, the memory elements 52 and 59 remain in this state even when the movable contact 79 is released and returned to the rest position.

In order to prevent the circular knitting machine from stopping due to short transient changes in the measurement signal, a delay RC element 81 with a longitudinal resistor 82 and a grounded capacitor 83 can also be provided in the line 48. In FIG. 3, the RC element 81 is shown as a dotted line, but this is to indicate that this RC element 81 can be used instead of the solid line 48. By selecting the time constant of this RC element 81, the signal pulses are filtered for a corresponding period, and both differential amplifiers 45, 46
before either responds, the measured signal is at a level that signals an error for a length of time defined by the time constant of RC element 81.

Therefore, there is no longer a very small voltage drop across the series of resistors 41 or its partial resistors 42a-42c.
Even if a large deviation occurs, the differential amplifiers 45, 46 will not be switched, and both differential amplifiers will be switched only when a large excursion occurs. For example, the output signal of differential amplifier 46 will not become positive until the non-inverting input is at a significantly positive voltage compared to the inverting input.

When offset compensation type differential amplifiers are used as the differential amplifiers 45 and 46, the bias signal circuit 4
4 allows the sensitivity to be varied through the connections shown at 84 and 85 in FIG. 3 without selecting a separate pickup with a series of resistors 41. The bias signal circuit can be switched around simply by supplying appropriate signals to the offset compensation input terminals 84, 85 connected in parallel.

From the above description in conjunction with FIG.
4'' and measuring circuits 36, 36', 36'', etc., the absolute value of the voltage on line 43 plays no role. Therefore, there is no need to switch the circuit system 35 to accommodate different yarn feed rates. For the same reason, the circuit system 35 will not report unwanted errors whenever all knits move uniformly in the same direction of decreasing yarn over time. Because circuit system 35
This is because it will only react if one of the knits consumes a significantly different amount of yarn than the rest. The circuit is thus protected from false alarms that would occur if each knit was compared to an absolute value of yarn quantity rather than to a varying yarn quantity reference value.

In the embodiment shown here, the amount of yarn supplied is checked, but instead of this, the tension of the yarn in all knitting sections may be checked. In this case, instead of the signal on line 33, VCO 27
The regulation signal of the VCO 27, which is applied to the input of the VCO 27, forms the basis of the measurement signal.

If the yarn supply means is mechanically driven by a belt or the like, appropriate yarn amount or yarn tension meters are attached to the yarn travel paths of the various knitting sections,
Extract the necessary electrical signals. The yarn supply unit 1 of FIGS. 1 and 2 is presented only as an example in this sense. The circuit system of the invention is not limited to being used in such an electrically regulated yarn supply unit 1.

Figure 5 adds another requirement to the circuit system in Figure 3 to not only allow the yarn supply sections to be compared with each other, but also to calculate the yarn consumption of the supply section at the rotational speed of the circular knitting machine. That is, it is designed to allow comparison with a reference value based on the operating speed. A comparator circuit 91 having a machine speed reference value generation circuit 92 and a bias signal circuit 44 is connected to the connection line 43.
It is connected to the. Since the bias signal circuit 44 has the same configuration as the bias signal circuits 44, 44', 44'' in FIG. 3, the components of the bias signal circuit 44 in FIG. 5 are also given the same symbols as in FIG. The above description regarding the configuration and function of the bias signal circuit in FIG.
This also applies to the bias signal circuit shown in the figure.

Machine speed reference value generation circuit 92 receives the rotation speed proportional signal via optimum rotation speed converter 93 .
This speed converter 93 is connected in a phase-locked manner to the drive system of the circular knitting machine and sends out on line 94 an electrical signal whose frequency is strictly proportional to the speed of the knitting machine. Since optical speed converters of this type are known, the speed converter 93 will not be described further.

The frequency signal thus obtained is supplied via line 94 to a frequency-to-voltage converter 95,
It is converted into an analog signal whose amplitude is proportional to frequency. Since frequency-voltage converters are also well known, the internal structure will not be described in detail. The output of frequency-to-voltage converter 95 is supplied via line 96 to amplifier device 97 . Amplifier 97 begins at voltage divider 37 and extends to a series of resistors 41, and includes measuring circuits 36, 3 in FIG.
6', 36'', etc. Therefore, what has been said about the structure and function of this device in connection with FIG. 3 also applies to the amplifier device 97. The only difference is that the voltage divider The hot end of 37 receives a signal from line 96 that is proportional to the rotational speed of the circular knitting machine, rather than a signal from line 33 that is proportional to the amount of yarn supplied or a signal from line 26 that is proportional to the tension of the yarn. is provided.

On the one hand, the comparator circuit 91 makes a small contribution to the yarn quantity reference value of the connecting line 43, which is connected, for example, to other measuring circuits 36, ..., 36'', and on the other hand, the bias signal circuit of the comparator circuit 44 inspects the rotation speed proportional signal value preset at the output 39 using the spun yarn amount reference value present in the connection line 43.The reference value of the connection line 43 is determined by Since it is independent of the feed rate, it increases in proportion to the rotational speed of the circular knitting machine, assuming that the circular knitting machine is properly adjusted. The machine speed reference value increases in the same way.The machine speed reference value is therefore the logical yarn consumption of a circular knitting machine, and this and the varying yarn quantity reference of line 43 are shown in FIG. The bias signal circuit 44 of FIG.

In this comparison, if an excessive excursion occurs, characterized by a voltage drop across the series of resistors 41, the excursion signal circuit 44 of the comparator circuit 91 generates a machine stop signal at the output terminal 72, and the LED 57 and 67 indicates whether the actual yarn consumption is above or below the value fixed by the machine speed reference value.

The bias signal circuit of each yarn user has at least one comparator whose input terminals constitute input terminals of the bias signal circuit. This voltage is either the total voltage drop across the series of resistors forming the maximum sensitivity, or the voltage across some of the resistors reducing the sensitivity. Therefore, before the bias signal circuit generates an error or bias signal, it does not matter whether the yarn tension or the yarn supply amount deviates significantly upward or downward from the yarn amount reference value. Another way to change the sensitivity of the bias signal circuit is to change the offset voltage of the comparator. With this type of configuration, all bias signal circuits can be changed with a single electrical signal.

In a simple case, the same specific resistance of all measuring circuits can be obtained by providing the signal output stage with a differential amplifier connected to a negative feedback potentiometer amplifier. This is because by doing so, the output wiring of the differential amplifier does not affect the specific output resistance. On the other hand, the sensitivity of the amplification, ie measurement circuit, is stable over long periods of time and is independent of the parameters of the differential amplifier within wide limits.

If a bias or error signal is to be generated with a value above or below a yarn rate reference value, the bias signal circuit requires two comparators to monitor for excessive thresholds in a fixed direction. One comparator monitors the upper threshold and the other comparator monitors the lower threshold.

In order to prevent the machine from stopping due to temporary changes in yarn tension or volume, the bias signal circuit is supplied with a delayed measurement signal.

Each bias signal circuit can be provided with a memory element that can be selectively reset externally and that can generate an error signal of any duration when the bias signal circuit first responds.

The operator of the knitting machine needs to know that in certain operating conditions he is not consuming yarn until a predetermined yarn consumption for the speed or rotational speed of the knitting machine is exceeded. In the device according to the invention, this requirement can be easily met by simply providing comparator means for comparing the yarn quantity reference value with the machine speed reference value based on the rotational speed of the knitting machine. The machine speed comparison means are identical in construction to the measuring means and bias signal circuitry provided in each yarn supply, in order to keep the circuitry and manufacturing costs as low as possible. The only difference is that a signal proportional to the rotational speed of the machine is supplied to the signal input terminal of the measuring circuit. The mechanical rotation speed converter constitutes a reference value generation circuit together with the measurement circuit. The reference value generation circuit has the same electrical parameters on the output side as the other measuring circuits and is connected to the first connection line via a series of resistors. The bias signal circuit of the comparison means has the same structure as the bias signal circuit associated with the yarn supply means and receives at its input terminal at least a portion of the yarn quantity reference value;
The other input terminal receives at least a portion of the machine speed reference value.

The machine speed reference value, which is generated via the comparison means and corresponds to the logical yarn consumption of the machine, depends on the one hand on the machine speed reference value and on the other hand on the feed rates of the various yarn supplies. An error or deviation signal is generated each time there is an excessive deviation from the yarn quantity reference value. The measurement signal obtained from the yarn supply means is
Since the number is larger than the machine speed reference value, it affects the yarn amount reference value.

Various changes and modifications may be made within the scope of the invention, and the features described above also apply to such changes and modifications.

[Effects of the Invention] As explained above, according to the present invention, by automatically monitoring the tension and supply amount of the spun yarn, various values regarding the tension and supply amount of the spun yarn can be set and desired values can be set. A yarn feed control device can be provided that eliminates the need for adjustment.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a spun yarn supply device according to an embodiment of the present invention, which is suitable for outputting signals indicating the tension and supply amount of spun yarn, and FIG. 2 is a perspective view of the spun yarn supply device of FIG. 1. FIG. 3 is a block diagram showing a first example of a control circuit system for a yarn supplying device of the present invention that monitors the tension and supply amount of yarn.
The figure is a proxy circuit diagram to explain how the reference value for the amount of spun yarn is generated, and Figure 5 shows the spun yarn using the machine speed reference value corresponding to the rotation speed of the machine that uses the spun yarn. FIG. 3 is a block diagram showing a second example of a control circuit system for a supply device. 1... Spun yarn supply device, 12... Spun yarn, 21
... Electro-optical signal converter, 36, 36', 36''...
...Measurement circuit, 39, 39', 39''...Output terminal,
44, 44', 44''...bias signal circuit.

Claims (1)

[Scope of Claims] 1 A plurality of spun yarn supply means 1, a plurality of spun yarn use sections that receive spun yarn supply from the spun yarn supply means, and the spun yarn supply means and the spun yarn use section. a plurality of detecting means 21, 22 that contact the spun yarn 12 moving between them and generate a spun yarn supply parameter signal; During the supply of yarn to the section, output terminals 39, .
..., 39'', a plurality of measuring circuits 36, ...,
36'', in a yarn supply control device for controlling the supply of yarn 12 to an apparatus using yarn, such as, in particular, a circular knitting machine with multiple feed devices, having a predetermined plurality of said measurements. reference signal generating means 38, 41, . . . , 41″, which are connected to the circuit and generate a reference signal dependent on all the output signals from the plurality of measuring circuits 36, .
43, attached to each yarn supply means, receiving (a) said reference signal and (b) said output signal from said measuring circuit connected to each yarn supply means;
Bias signal circuit 4 generating a bias signal as output
4, . A spinning yarn supply control device characterized by: 2. The reference signal generating means has a predetermined specific resistance, and the output terminal 3 of the measuring circuit 36,..., 36''
A series of resistors 41,...,4 connected in series between 9,...,39'' and the first connection line 43
1'', the measuring circuits 36,...,36'' all have their output terminals 39,...,39'' connected to the first connection line 43 via the series of resistors 41,...,41''. The yarn supply control device according to claim 1, characterized in that the other output terminal is connected to a common second connection line (circuit ground). 3. Each series of resistors 41;...;41'' consists of at least two series-connected partial resistors 42
a,...,42c;...;42a'',...,42
3. The yarn supply control device according to claim 2, characterized in that the yarn supply control device has the same characteristic as that of the measuring circuits 36, ..., 36''. The yarn supply control device according to claim 2. 5. The yarn supply control device according to claim 2, wherein the series of resistors 41, . . . , 41'' are all identical. 6. Each measuring device 36; 2. Yarn supply control device according to claim 1, characterized in that the stage comprises a differential amplifier (38) wired as a negative feedback potentiometer amplifier. 7. Each bias signal circuit 44;...;44'' has at least one comparator 45, 46, both input terminals of which constitute input terminals of the bias signal circuit 44;...;44''. The spun yarn supply control device according to claim 1, characterized in that: 8. Each bias signal circuit 44;...;44'' has at least one comparator 45, 46, both input terminals of which constitute input terminals of the bias signal circuit 44;...;44''. 41'', and a voltage proportional to the voltage drop across the associated series of resistors 41;
3. The spinning yarn supply control device according to claim 2, wherein the yarn is supplied between 48 and 48. 9 The voltage drop that occurs across each series of resistors 41;
...; Corresponding partial resistors 42a, ... in 41''
9. The spinning yarn supply control device according to claim 8, wherein the voltage drop is at...;42c,...;42a'',...,42c''. 10 the comparator 45 influencing the output signal;
8. A yarn supply control system according to claim 7, characterized in that said comparators (45, 46) are provided with offset adjustment means for varying the voltage difference at the inputs of said comparators (45, 46). 11 Each bias signal circuit 44;...;44'' for checking whether the vertical fluctuation of the measurement signal with respect to the yarn amount reference value is within the range of the allowable error value,
The yarn supply control device according to claim 1, characterized in that it has two comparators (45, 46). 12. Yarn supply control device according to claim 1, characterized in that each bias signal circuit 44; ...; 44'' has a memory element 52, 59. 13 Each bias signal circuit 44; ...; ;44'' comprises memory elements 52, 59, said memory elements 52, 59 being connected to the output terminals of the associated comparators 45, 46. Yarn supply control device. 14. The yarn supply control device according to claim 1, characterized in that a time delay and pulse filtering element 80 is provided upstream of the input terminal of the bias signal circuit 44;..., 44''. 15. The yarn supply control device according to claim 1, wherein each measuring circuit 36;...;36'' has a sensitivity adjustment means 37. 16. The spun yarn supply according to claim 1, further comprising comparison means 91 for comparing the spun yarn amount reference value and a machine speed reference value that depends on the rotational speed of the machine using the spun yarn. Control device. 17 The comparison means 91 has a machine speed reference value generation circuit 92 and a bias signal circuit 44, and the signal output terminal 39 of the machine speed reference value generation circuit 92
has a defined inherent output resistance, and the bias signal circuit 44 has two input terminals 47, 48, one of which receives at least a portion of the yarn amount reference value. The other input terminal is supplied with at least a part of the output signal of the machine speed reference value generation circuit 92, and the bias signal circuit 44 is configured to output a signal from the machine speed reference value and the yarn amount reference value to each other. 17. The yarn supply control device according to claim 16, wherein an error signal is generated whenever the deviation of the yarn exceeds a predetermined value. 18 A series of resistors 41 connected to the first connection line 43 connect the machine speed reference value generation circuit 9
18. The spinning yarn supply control device according to claim 17, wherein the spinning yarn supply control device is connected in series to the second output terminal 39. 19 The series of resistors 41 comprises at least two series connected partial resistors 42a, . . . , 42
The spinning yarn supply control device according to claim 18, characterized in that it has c. 20. Claim 1, wherein the specific output resistance of the machine speed reference value generation circuit 92 is equal to the specific output resistance of the measurement circuits 36, ..., 36''.
7. The spinning yarn supply control device according to 7. 21 The series of resistors 41 of the machine speed reference value generating circuit 92 are connected to the measuring circuits 36,...,3
20. Yarn supply control device according to claim 19, characterized in that it is the same as a series of resistors 41, . . . , 41" of 6". 22. The yarn supply control device according to claim 17, wherein the machine speed reference value generation circuit 92 has a differential amplifier 38 wired as a negative feedback potentiometer amplifier as a signal output stage. . 23 The bias signal circuit 44 of the comparator circuit 91 includes at least one comparator 4 whose input terminals constitute input terminals of the bias signal circuit 44.
Claim 1 characterized in that it has 5.46.
7. The spinning yarn supply control device according to 7. 24 The voltage corresponding to the voltage drop across the series of resistors 41 of the machine speed reference value generation circuit 92 is
The spinning yarn supply control device according to claim 23, wherein the voltage is applied between both input terminals 47 and 48 of the comparators 45 and 46. 25. The voltage drop across the series of resistors 41 is the voltage drop across the partial resistors 42a, . . . , 42c of the machine speed reference value generating circuit 92. Yarn supply control device. 26 the comparison means 91 influencing the output signal;
Yarn supply according to claim 23, characterized in that offset adjustment means 94, 95 are provided in the comparators 45, 46 for a change in the voltage difference at the inputs of the comparators 45, 46. Control device. 27 Each bias signal circuit 44 has two comparators 45 and 46 for checking whether the vertical fluctuation of the machine speed reference value with respect to the yarn amount reference value is within a tolerance value. The spinning yarn supply control device according to claim 17, characterized in that: 28 Each bias signal circuit 44 has a memory element 52,5
18. The spun yarn supply control device according to claim 17, characterized in that it has a number 9. 29 Each bias signal circuit 44 has a memory element 52,5
9, and the memory elements 52, 59 have corresponding comparators 4
29. The spinning yarn supply control device according to claim 23, wherein the spinning yarn supply control device is connected to output terminals 5 and 46. 30 the bias signal circuit 44 of the comparison means 91
Yarn supply control device according to claim 17, characterized in that a time delay and pulse filtering element (81) is provided upstream of the input terminal of. 31. The yarn supply control device according to claim 17, wherein the machine speed reference value generation circuit 92 has a sensitivity adjustment means 37. 32 The reference signal generating means 38, 41,...,
41'', 43 are all measurement circuits 36, ..., 3
Claim 1 characterized in that it is connected to 6″.
The spinning yarn supply control device described in .